An anti-immigration rights protester, left, holds up a sign as he is pointed at and shouted at by immigration rights marchers during a Puente Movement event in Phoenix. / Ross D. Franklin AP

by Alvaro Vargas Llosa, USA TODAY

by Alvaro Vargas Llosa, USA TODAY

Apart from the fiscal mess, no legislative priority is greater than immigration reform. It should be passed this year, before the president becomes a lame duck, the 2014 midterm elections get in the way and the current bipartisan goodwill on this issue fades.

The last few years have dealt a devastating blow to the arguments used to postpone comprehensive immigration reform -- especially the notion that the border needs to be "secured" first.

Immigration has already fallen dramatically. In the case of Mexicans, net immigration had dropped to zero by 2011 and is likely negative by now -- meaning more Mexicans are going home than coming to the United States. The result: The number of undocumented Mexicans declined by almost 1 million between 2007 and 2011.

What is the main cause of this? While other factors may be at play, including improving conditions in Mexico, the main reason appears to be the weak economy. People aren't coming because the U.S. economy is producing too few jobs.

Tightened border security appears to have played little role. Despite a sharp increase in border patrol activities since 2000, including passage of the Security Fence Act of 2006, prior to the 2007 economic collapse the 10 states with the most immigrants saw their undocumented populations rise by half a million. But as soon as the recession set in, the number of illegal entries dropped by two-thirds and requests for H1-B visas -- temporary work permits primarily for technology workers -- decreased as well. This is consistent with what happened after the bursting of the dot.com bubble in 2000.

Opponents of comprehensive reform are now on the defensive. Zero or negative net immigration means either that the border is as secure as it will ever get in a democracy, or that immigration is so much more sensitive to the economy than to enhanced security that further efforts to secure the border are senseless.

Republicans have a vested interest in passing immigration reform as soon as possible. To judge by the GOP vote among Hispanics and Asians, continued opposition to immigration reform could be suicidal. While Latinos constituted 5% of the total vote in 1996, they represented 10% in the 2012 presidential elections. Together, Hispanics and Asians supported Democrats by a three-to-one margin.

If the perception persist that Republicans are anti-immigrant, Hispanics could become a permanent Democratic constituency.

This doesn't have to be. Earlier Republican leaders enjoyed strong Hispanic support, including Ronald Reagan and George W. Bush, both of whom received close to 40% of the Latino vote.

The argument that legalized immigrants will become permanent Democrats mistakes the symptom for the cause. The cause of the disproportionate Democratic support is not party loyalty, but fear that Republicans are against immigrants. The Democratic support is a symptom of that fear. Postponing reform will deepen it.

The economic and cultural arguments against putting undocumented immigrants on a path to citizenship, and welcoming newcomers in the future, also have been disproved by reality.

Rather than take away native jobs, foreign workers have helped enlarge the economic pie. Economist Benjamin Powell, a senior fellow with the Independent Institute, with which I am affiliated, estimates that immigrants, legal and undocumented together, add at least $36 billion per year net to the U.S. economy.

Nor have the millions of undocumented workers caused long-term unemployment to rise. Consider Arizona. Before 2008, undocumented foreigners made up 10% of Arizona's 3-million-plus work force. But unemployment at the beginning of the year was a mere 4%. In other words, they were filling a vacuum, not pushing natives aside.

Culturally, immigrants are not much different from natives either. They are overwhelmingly religious, highly entrepreneurial and largely family-oriented, with approximately half of all immigrants living with a spouse and child. Perhaps all this explains why acculturation patterns are similar to those of previous waves of immigrants.

The opportunity for reform must be seized this year, before the political opportunity passes.

Previous reforms failed because they created inflexible quota systems. Needed instead is flexibility: a system that responds to the needs of the economy, rather than the whims of bureaucrats and politicians.

Alvaro Vargas LLosa is a senior fellow at the Independent Institute. His new book, "Global Crossings: Immigration, Civilization and America," will be published in June.

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